Trends within the field of packaging machines point towards increasingly high capacity machines intended for rapid, continuous production of a very large number of identical or similar packaging containers, e.g. such as are intended for liquid contents such as milk, juice and the like. However, even though the various functions of such packaging machines are greatly integrated with a view to restricting the size of the machines, the space requirements continue to grow. The state-of-the-art generation of high capacity filling machines for, for example, milk, are of such size that, for reasons of space, they that are often incapable of replacing an older machine of lower capacity but instead require as much space as two such prior art models. In addition, from the point of view of capacity, two slower machines may occasionally be comparable with a single modern high capacity machine and, moreover, afford a higher degree of flexibility when it comes to the simultaneous manufacture of packaging containers of different sizes or types, or packaging containers which are to be filled with different types of liquid contents.
Many of the prior art packaging machines which are currently in operation on the market manufacture single-use disposable packages of laminated, plastic-coated fiber material which, in the form of flat-laid blanks, is fed to a magazine in the packaging machine. Each packaging container blank is transferred from the magazine to a mandrel which serves as backup counterface when the one end of the packaging container blank is folded down and heat-sealed for forming a liquid-tight bottom in the packaging container. The blank is then placed in a conveyor which is advanced stepwise so that the blank passes stations for top-forming, filling and top-sealing, whereafter (possibly after final forming) it is discharged from the packaging machine in the form of a filled and sealed packaging container. The stepwise advancement in the transport sequence is restricted--in both frequency and speed--by the fact that the packaging containers which are located between the filling station and the top-sealing station are filled with their liquid contents, which may easily be set in motion and slop over the upper, open end of the packaging container if the indexing in the transport sequence becomes too rapid or jerky.
A further drawback inherent in prior art machines of the above-outlined type is that they are exclusively intended for the manufacture of packaging containers of one type--and moreover are often limited such that they can only produce the selected type of packaging container in a single size. Even if it were theoretically possible, by replacing and rebuilding certain parts of the packaging machine, to manufacture packaging containers of, for example, a different top design configuration, this often defies ready technical application without extensive retrointervention in the packaging machine, since the various parts of the machine are not only integrated with one another to a considerable extent, but are also driven by a common prime mover or power source by the intermediary, for example, of one drive shaft with a number of cam surfaces.
It will be apparent from the foregoing discussion that it is a general wish within the art to devise a packaging machine for manufacturing packaging containers for liquid contents which in itself combines the three properties of high capacity, slight space requirements and extreme versatility. Naturally, account must also be taken of a number of other factors of well-known type, for example the overall capital costs of the machine, serviceability, operational reliability and demands on standards of hygiene.